Among the many devices which are adapted to deliver gas, fluid or further medicaments, to the lung, metered inhalers are widely used. Several patents describe metered inhalers for delivering gas, fluid or medicaments.
U.S. Pat. No. 4,017,007 discloses an air pressure-operated dispenser for spraying a single dose of a fluent material of liquid or powder form. The dispenser has a single dose container having a compressed air inlet opening and a closable discharge orifice and means for closing the discharge orifice in a non-dispensing position of the dispenser. An air-compressing piston pump having a compressed air outlet from a compression space thereof is further provided on the dispenser at the junction of the inlet opening and the compressed air outlet.
The inlet opening of the single dose container is joined to the compressed air outlet of the compression space and valve means is provided on the piston pump for releasing a flow of compressed air.
U.S. Pat. No. 5,893,515 discloses a device for generating a spray of mist or fine droplets includes a spinning rotor within a mist chamber. The rotor has inner walls which taper conically outwardly from the open bottom of the rotor to a hole near the top of the rotor.
Liquid is pumped by a finger actuated pump from a cartridge module into a bowl surrounding the bottom end of the rotor. The spray is created as the liquid is formed into droplets as it passes through the hole in the rotor under centrifugal force.
PCT patent application No. 2004011068 discloses a medicament dispenser device for use in the delivery of a combination medicament product. The dispenser comprises a first medicament container for containing a first medicament component, a first release means for releasing the contents of said first medicament container, at least one medicament container for containing at least one further medicament component, and at least one release means for releasing the contents of at least one medicament. The first medicament component is kept separate from the at least one further medicament component until the point of release thereof for delivery in combination. The dispenser additionally comprises an electronic control system for controlling the release of contents from the medicament container.
EP patent application No. 1689474 discloses an inhaler which comprises a compressed gas, in a first chamber which is in communication with an equalization chamber having pressure lower than the pressure of the gas in the first compressed chamber and having a drug storage chamber which is detachably coupled to the equalization chamber operable such that a portion of the compressed gas from the equalization chamber fluidizes and aerosolizes the drug to produce a drug cloud and which can then be injected into a spacer where it can be inhaled by a user.
PCT application No. 1999021659 discloses a device and a method of reducing the droplet size of a composition sprayed from an aerosol spray device comprising a compressed gas propellant, which method comprises imparting a unipolar charge to the liquid droplets by double layer charging during the spraying of the liquid droplets from the aerosol spray device, the unipolar charge being at a level such that the droplets have a charge to mass ratio of at least +/−1×10<−4> C/kg.
The above-described devices are electrically powered, less portable or provide long treatment time. It therefore remains a long felt and unmet need to provide novel means and methods for an inhaler device which generates and delivers a dose of gas, fluid or a mixture thereof in a more effective and short term manner.